激素治疗风湿病患者股骨头骨坏死风险评估的MRI研究

摘要

目的 观察激素治疗风湿病患者髋部骨及骨髓的MRI表现,分析MRI在股骨头坏死风险评估中的意义.资料与方法 激素治疗的50例风湿病患者行髋关节X线平片及冠状位MRI检查,MRI检查序列包括自旋回波T1WI、脂肪抑制序列(STIR)、动态增强扫描(DCE-MRI).采用股骨骨髓转化系数(MCI)值及DCE-MRI时间-信号强度曲线定量分析激素治疗未发生骨坏死患者股骨骨髓的信号强度及血流灌注；并选取同期年龄相匹配的20例正常志愿者作为正常对照组.结果 50例患者中,5例(6髋)发生股骨头坏死,其中1例为双髋.20例未发生骨坏死的激素治疗患者与正常对照组( 79.51±6.58)相比,股骨MCI明显增高(90.41±5.23),差异有统计学意义(t=4.10,P＜0.01)；两组干骺端及股骨头的血流灌注差异有统计学意义(t=4.47,P＜0.05；t=5.12,P＜ 0.05).结论 MRI股骨骨髓转化系数及DCE-MRI是评估股骨头骨坏死风险的有效手段,可为股骨头坏死的临床研究提供影像学依据.%Purpose To observe bone and marrow in the femur of rheumatisant treated with steroids with MRI, and to analyze the value of MRI in risk assessment of osteonecrosis of femoral head (ONFH). Materials and Methods Hip MRI and X-ray plain film were performed in 50 rheumatisant patients. MR imaging of femur was obtained by the short time inversion recovery, Tl weighted spin echo technique and dynamic contrast-enhanced MR imaging (DCE-MRI). The marrow conversion index (MCI) was the ratio of the marrow signal intensity of the proximal femoral metaphysic (SM) to that of the greater trochanter (ST). The difference of signal intensity and blood perfusion in femur was compared between rheumatisant treated without steroid and normal volunteer. Results Among 50 patients, there were 5 cases with ONFH, bilateral ONFH (n=l), unilateral ONFH (n=4). 20 cases without ONFH had higher values of MCI than that of age matched normal volunteer. There was statistical difference of statistical in the two groups (t=4.10, P<0.01). The values of Emax which was used to evaluate blood perfusion in metaphysic and femoral head were different between case without ONFH and normal group (/=4.47, 5.12, P<0.05 respectively). Conclusion The values of MCI and DCE-MRI are the available technique in risk assessment of ONFH and imaging information in research of prevention ONFH.